So while I am contemplating my final colour scheme for this helmet (MP team orange inspired or gun metal grey), I did some prep on my side lights.
I am not aiming on any hardcore lighting, just the effect/illusion based off two detailed holes per side with mini flashlights peaking through.
I found some steel "1/4 countersunk style finishing washers" for $0.17 a piece, I roughed them up with 60 grit sandpaper for priming and due to a recess behind the washer - had room to place tinted plastic to complete the look.
Have not painted then yet but using spare material and these washers, off to a good start.
1. Dry fit, held in place with the existing primer paint
2. 3 items needed - washer, tint (in this case 5% and piece of plastic
3. Demo showing light shine through